My right knee popped out of place. its very sore and hurts to walk. what should i do?

Get it put back: Well, if you're sure it hasn't gone back into its place spontaneously (often happens quickly after it pops out) and if you are sure that it is actually out of place and not just injured then, your only option is to get thee to emergency-- or to a trainer if you are a college student or athlete. There will be residual pain after it gets back into place so don't expect that to go away immediately.